* add first data driven tests
* remove unused mock
* test unique_id migration
* test errors during setup
* test error during data update
* test update entity
* system_versionis always available
* make use of snapshot_platform helper
* use parametrize test for coordinator update errors
* apply suggestions
* don't touch internals on coordinator tests
* rework to use async_get_or_create instead of mock_registry
Michael